Saracens make four changes from the side which narrowly beat Ospreys in the European Champions Cup last weekend.

Scrum-half Ben Spencer and Nick Tompkins return in the back line while prop Vincent Koch and flanker Schalk Burger are named in the pack.

Irish have kept faith with seven players who were part of the 44-7 win at Stade Francais in the European Challenge Cup on Saturday.

Joe Cokanasiga and Tom Fowlie start on the wing and centre respectively.

Saracens: Goode; Williams, Tompkins, Barritt (capt), Wyles; Farrell, Spencer; Vunipola, George, Koch, Isiekwe, Kruis, Clark, Burger, Wray.

Replacements: Tolofua, Barrington, Figallo, Skelton, Earl, Wigglesworth, Lozowski, Earle.

London Irish: Bell; Cokanasiga, Fowlie, Mulchrone, Lewington; Marshall, Meehan; Franks, Paice (capt), Du Plessis, Van der Merwe, Paulo, McNally, Cowan, Treviranus.

Replacements: Woolstencroft, Elrington, Hoskins, Schatz, Northcote-Green, Steele, Brophy Clews, Ojo.

Northampton make three changes from the Champions Cup defeat by Clermont for the visit of Wasps.

Full-back Ahsee Tuala replaces Harry Mallinder, while forwards Kieran Brookes and Jamie Gibson are recalled.

Wasps bring in Guy Thompson at number eight in place of the suspended Nathan Hughes, who starts a two-week ban.

With Wasps still missing 11 injured players, that is the only change to the starting line-up that beat Harlequins 41-10 in the Champions Cup on Sunday.

Wasps start the day in 10th, having lost four of their Premiership games this season - 10 points behind third-placed Northampton.

Northampton: Tuala; Foden, Tuitavake, Burrell, Collins; Francis, Groom; Waller, Hartley (capt), Brookes, Lawes, Ratuniyarawa, Gibson, Wood, Harrison.

Replacements: Haywood, van Wyk, Hill, Day, Paterson, Reinach, Mallinder, Pisi.

Wasps: Le Roux; Wade, Daley, De Jongh, Bassett; Gopperth, Robson; Mullan, Johnson, Cooper-Wooley, Launchbury (capt), Rowlands, Haskell, Young, Thompson.

Replacements: Harris, McIntyre, Moore, Gaskell, Willis, Symons, Simpson, Miller.

Harlequins make six changes from the side beaten by Wasps as Mark Lambert replaces banned prop Joe Marler and hooker Elia Elia makes his first start.

Prop Will Collier and flanker James Chisholm return from injury, with Alofa Alofa named at centre.

Bottom club Warriors, without England's Ben Te'o, make four changes as they seek a first league win of the season.

Skipper Donncha O'Callaghan, winger Perry Humphreys, hooker Joe Taufete'e and flanker Sam Lewis all return.

Front row Ethan Waller, Gareth Milasinovich and Taufete'e, who scored a first-half hat-trick of tries in the European Challenge Cup win over Brive,are all handed a first Premiership start of the season, as is Australian stand-off Jono Lance.

Lewis deputises for former Warriors captain GJ van Velze, who is missing after suffering a head injury last weekend - his first setback since missing almost the whole of last season with a concussion problem.

Harlequins: Brown; Walker, Alofa, Roberts, Visser; Smith, Care; Lambert, Elia, Collier, Glynn, Horwill (capt), Chisholm, Robshaw, Luamanu.

Replacements: Piper, Boyce, Swainston, Matthews, Lamb, Mulchrone, Swiel, Sloan.

Worcester: Pennell; Humphreys, Olivier, Willison, Adams; Lance, Arr; Waller, Taufete'e, Milasinovich, O'Callaghan (capt), Spencer, Faosiliva, Lewis, Denton.

Replacements: Singleton, Bower, Alo, Phillips, Taylor, Dowsett, Heathcote, Howe.